1. Field of the Invention
The present invention is related to the field of bird feeders and, more particularly, to a top-fill hummingbird feeder.
2. Description of the Related Art
People who live in an area inhabited by hummingbirds frequently try to promote their presence by the use of hummingbird feeders. Hummingbird feeders differ from ordinary bird feeders because hummingbirds feed on nectar or simulated nectar, which are liquid, instead of the seeds or other dry food consumed by most birds from bird feeders. Simulated nectar is typically formed from water sweetened with sugar or honey. In many hummingbird feeders, the nectar (or simulated nectar) is stored in a reservoir and conveyed to simulated flowers where a perch may be provided so that the hummingbird can land and, having a long, slender beak, insert it into the access apertures in the simulated flower and feed.
Most hummingbird feeders have one of two basic designs. One includes an inverted top container which empties into a lower reservoir or feeding basin from which the birds feed. The vacuum at the top of the container (or put another way, the outside air pressure) keeps the liquid in the top container from draining too rapidly out of the feeding basin. The other common feeder design consists of a container with holes in its cover through which the hummingbirds reach to feed. This latter style of feeder suffers from the problem that it must be refilled very often, because the level of food is constantly being reduced by the feeding.
The so-called “vacuum-type” feeders also have problems. For example, they can only be filled by dismantling the feeder and removing the top container from its feeding position. Ordinarily, the consumer must invert the feeder in order to refill it, with the attendant risks of spillage, and requires a certain amount of manual dexterity to create the necessary vacuum. Moreover, because a vacuum is required, these designs are limited to a single opening for filling and cleaning. This opening is typically small, which restricts access to the interior of the container and makes it more difficult to effectively clean the container. Additionally, vacuum feeders can corrode or be inefficient, permitting the nectar to leak and creating an increased risk of insect contamination.
One product which has been available in the market is the Garden Song Top Fill Hummingbird Feeder from Opus Incorporated, now marketed by the assignee of the instant invention. The Opus feeder includes an upstanding liquid container with a large top opening and a small cylindrical lower opening which is screw-threaded into an upstanding cylindrical collar positioned in the center of a feeding basin or liquid tray. The top opening is closed with a cover that seals the container to create a vacuum as the liquid level recedes downwardly in the container. An internal, rotatable ring or valve mechanism has an upstanding cylindrical wall which surrounds the aforesaid cylindrical collar inside the feeding basin.
The wall of the cylindrical collar has a plurality of ports, and the cylindrical wall of the rotatable ring has a plurality of corresponding openings. When the openings in the rotatable ring are aligned with the ports of the collar using an externally accessible lever, nectar can flow out of the container lower opening, through the aligned ports and openings, and into the feeding basin or liquid tray. When the rotatable ring is rotated using the externally accessible lever, so that its openings are not aligned with the ports of the collar, the nectar flow from the container to the feeding base is cut off. In this condition, the cover can be removed from the container top opening for (re)filling the container without nectar in the container flowing out through the collar to flood and overflow the feeding base or liquid tray. This design also permits the top opening to be large enough to facilitate easy cleaning of the bottle. However, the rotational sealing design of the Opus feeder does not provide the user with a positive indication of the feeder having been placed into the open and/or closed positions.
Another top-fill style hummingbird feeder is set forth in co-pending application Ser. No. 11/785,905, also owned by the assignee of the instant invention. This hummingbird feeder includes a generally upstanding reservoir bottle having a large opening at its top end that is sealed by a removable top or cap. The bottom of the bottle or container has a lower bottom opening which can be screw-threaded into a central collar of a feeding basin that has a plurality of feeding ports in a known arrangement. An upwardly biased sealing mechanism is connected to the bottom end of an actuator rod positioned longitudinally down the center of the reservoir bottle. The sealing mechanism and actuator rod are operatively movable between a down position and an up position by screw-threading the removable top onto and off of, respectively, the reservoir bottle top open end. When the actuator rod and the sealing mechanism move to the down position by closing the top cap, the sealing mechanism opens the bottle lower opening and allows the flow of liquid nectar out of the reservoir bottle into the feeding basin. When the actuator rod and sealing mechanism move to the up biased closed position by removing the top cap, the sealing mechanism seals off the bottle lower opening and prevents liquid nectar from flowing out of the bottle into the feeding basin.